Billing software for SEO and marketing agencies
Retainers that invoice themselves, out-of-scope hours billed on the same invoice, ad spend kept separate from your fee, and reminders that chase payment without an account manager doing it. Unlimited clients from $15/month.
What agency billing actually requires
Agency billing is not one invoice to one customer. It is recurring revenue, variable overage, and pass-through costs across a portfolio of clients — every month.
Retainer billing on autopilot
Set a monthly retainer per client once. Invoices generate, send, and chase themselves on the same date every month, so recurring revenue stops depending on someone remembering.
Billable hours and overage
Bill the retainer, then add the hours that went beyond scope as separate line items on the same invoice — with the description the client can actually approve.
Project and campaign line items
One invoice, itemised by campaign, channel, or deliverable: SEO retainer, paid media management fee, content production, ad spend pass-through.
Many clients, one dashboard
No per-client limits and no plan upgrade when you land account eleven. Every client, invoice, estimate, and payment status in one place.
Receivables you can forecast
See what is billed, what is overdue, and by how many days — per client and in total — so you know payroll is covered before the month starts.
Cross-border clients
Multi-currency invoicing and country-correct tax fields for agencies with clients in the US, UK, EU, and beyond, including e-invoicing mandate formats.
How different agencies bill
SEO agencies
Monthly retainers per client, plus one-off technical audits and migration projects. Invoice the retainer automatically, add audit work as a line item, and keep ad-hoc consulting hours separate from scope.
Paid media and performance agencies
Management fee, percentage-of-spend, and ad spend pass-through on one invoice — clearly separated so the client sees exactly what is your fee and what is media.
Creative and content studios
Deposit up front, milestone invoices during production, balance on delivery — with deliverables remaining your property until the final invoice clears.
The five things that cost agencies money
Retainer invoices go out late because they are built manually each month.
Recurring invoices send on a fixed schedule, so the first of the month is not a task.
Scope creep is delivered but never billed.
Overage hours attach to the retainer invoice as separate, defensible line items.
Chasing payment eats account-manager time.
Automatic reminders escalate on their own schedule before, on, and after the due date.
Client count is capped by the invoicing plan.
Unlimited clients on one plan — growth does not trigger a pricing tier.
Ad spend pass-through inflates apparent revenue.
Pass-through lines are itemised separately from fees for clean reporting.
Invoicemonk vs typical agency invoicing plans
| Capability | Invoicemonk Pro | Typical alternative |
|---|---|---|
| Recurring retainer invoicing | Included | Higher tiers only |
| Client limit | Unlimited | 5–50 by plan |
| Automatic payment reminders | Included | Often paid add-on |
| Multi-currency invoicing | Included | Higher tiers only |
| Entry price | $15/month | $19–$35/month |
Alternative pricing reflects publicly listed entry plans and can change; check the vendor's current pricing page before deciding.
Frequently asked questions
What is the best billing software for an SEO agency?
An SEO agency needs recurring retainer invoicing, billable-hour overage on the same invoice, unlimited clients, and automatic payment reminders. Invoicemonk includes all four from $15/month with no per-client cap, which is why it suits agencies billing 10–100 retainer clients.
How do agencies bill monthly retainers?
Set the retainer amount and billing date per client, invoice on the same day each month in advance of the work, and add any out-of-scope hours as separate line items. Recurring invoicing sends and chases these automatically so retainer revenue arrives on a predictable date.
How should an agency invoice ad spend pass-through?
Keep the management fee and the media spend as separate line items, label the pass-through explicitly, and show the fee basis (flat or percentage of spend). This keeps client reporting clean and stops pass-through from inflating your revenue figures.
Can Invoicemonk handle both retainers and project work for the same client?
Yes. A client can carry a recurring retainer and separate project or milestone invoices at the same time, and both appear in one receivables view per client.
What payment terms should an agency use for retainers?
Most agencies invoice retainers in advance on Net 15 or due-on-receipt terms so the month is funded before the work happens. Project work is more commonly Net 30 with a deposit up front.
Bill every retainer on time
Recurring invoices, overage line items, unlimited clients, and automatic reminders — from $15/month.
Get started with Invoicemonk